Increasingly the prospect of electoral reform is the cause of bewildered anxiety and raging calculation across the political spectrum. The cuts are the overwhelming theme of this parliament but the divide that arises from them is fairly predictable and straightforward. In striking contrast, the referendum on a change to the voting system has the scope to shake up politics in ways that are explosively unpredictable. The parliamentary battle is about to intensify. The opposing campaigns are in place and are planning their first moves. No one quite knows what will follow.
The parliamentary divide is in itself weird. The Liberal Democrats back the change to the Alternative Vote even though they have never been supporters of this particular electoral system. Labour entered the last election supporting AV. Now it is the most anguished of the parties in relation to the issue. The Conservatives are opposed, even though some of them delight in their new partnership with the Liberal Democrats. There were even rumours that the likes of Oliver Letwin, a close ally to David Cameron, would campaign for a "Yes" vote. The rumours are untrue. Letwin will join the rest of the Tory ministerial team in opposing their new friend Nick Clegg.
In spite of Labour's sudden doubts Ed Miliband will support a change, but he has some big decisions to make, such as whether he will allow other shadow cabinet members to express their opposition, an "agreement to differ" as Harold Wilson called it when his Cabinet took opposite sides on Europe in the 1975 referendum.
Labour's intense wariness relates partly to the bill that gives the go ahead to the referendum. In the same legislation there is a separate proposal to change constituency boundaries in order to make them more equal in terms of population. The number of seats will be reduced to around 600.
According to senior shadow cabinet members this is the precise figure that benefits the Conservatives most. If the tally went below or above 600 the Conservatives would start to lose out. So a referendum aimed at making the voting system "fairer" is linked to another change that is included on the assumption that the Conservatives will gain around at least 30 seats.
Tories insist the change is long overdue but their move unites Labour in suspicious fury. The mild-mannered old friend of Tony Blair's, Charlie Falconer, plans to lead the onslaught in the Lords, convinced that the move is an example of gerrymandering of the worst kind. Ed Balls hinted during the leadership contest that he would oppose a "Yes" vote if the referendum went ahead as part of the same legislative package as the boundary changes. Labour seeks to block the legislation in the Lords.
The combined legislative package casts fresh light on the negotiations that led to the creation of the Coalition. The prevailing orthodoxy suggests that Nick Clegg played a blinder, securing more than his party's electoral performance deserved. The actual narrative is more nuanced. Clegg was the sought-after partner and therefore had a strong hand that he played well. But the Conservative negotiators were the ones that played a blinder, the only team in those frenetic days that had given some detailed thought in advance to what they would seek to achieve in such talks. They got every item that they cared about and conceded ground in areas in which they were relaxed.
Voting reform is symptomatic. It is quite possible that the referendum on AV will be lost, but the Conservatives will achieve the boundary changes that will benefit them with the support of the Lib Dems.
I do not blame the Conservatives for acting out of self-interest. That is what parties must do. No leader is going to stand on a platform in which he or she declares: "Under my leadership I back proposals that will lose us seats." Self-interest drives the multi-layered calculations.
This is what makes Labour's position so fluid. Before the election it seemed its only hope of clinging to power was in arrangement with the Liberal Democrats. At the last moment Gordon Brown committed his party to a referendum on electoral reform.
Now, to Labour's bewilderment, realignment has taken place on the centre right, with the Liberal Democrats marching together with the Conservatives. Miliband and others must contemplate a strange contortion in which they campaign for a change in the voting system that would benefit Clegg and present him with possibly the best chance for him to renew his relationship with David Cameron for another term.
Nonetheless Cameron is opposed to AV. He has been known to point out that under such a system the Conservatives would have been almost wiped out in 1997, as would Labour in 1983. He does not rule out the possibility of a more permanent arrangement with the Lib Dems and has gently mocked those who worked on the assumption that realignment on the centre left was more likely. Still he hopes for a "No" vote and looks forward to boundary changes precisely calculated to deliver several more seats for the Conservatives under the existing system. In doing so he possesses the ultimate populist argument in this anti-politics age: "We want fewer politicians".
A senior pollster tells me he would bet his house on the referendum being lost for those who want a change to the voting system. I can see why he reaches such a conclusion. The well- resourced might of the Conservative party and most newspapers take on unpopular Liberal Democrats and an ambiguous, divided Labour party.
There are, though, two factors that the pollster has not fully taken into account. The first is the nature of the "Yes" campaign. It plans to address the anti-politics era too, by making it a community-based campaign, keeping a distance from the leadership of the Liberal Democrats and highlighting the range of its support instead. The second is the calculation Labour voters must make about where their self-interest lies. More voters in England supported the Conservatives in 2005 under Michael Howard's leadership. With the boundary changes that benefit the Conservatives, such an outcome would be more fully reflected in seats at the next election too. It will be harder for Labour to win outright under the existing system.
In spite of what seems like Clegg's growing love-in with Cameron/Osborne it is quite possible that Labour's interests are best served in the longer term by a new voting system and a relationship with the Lib Dems, or some Lib Dems. A sophisticated pitch, combined with fresh calculations about where a party's interest lies, makes a "Yes" campaign winnable.
Voters are self-interested too. Most Tory supporters will vote for a status quo that might still deliver them a landslide. Lib Dems will vote for change. If Labour supporters want above all to give Clegg a kicking they will form a brief alliance with Tory voters. If they want power in the near future they may be alert to the argument that the bigger party in the Coalition is their main opponent.
Personally I have supported change since observing the degree to which distorting landslide victories paralysed rather than liberated those nervy Labour governments. But the route is going to be murky, impure and of doubtful outcome. Forget about claims of "fair votes". This is a battle about power and it has already begun.